Printing with an r Pi is looking quite hopfull ,

I have a very early version of the pi and we did get it to run the peachy but not very well dew to the very very quite audio and a big dc off set
We here that the newer r pi's have better audio, and if not there is alwase usb audio.

Id say we are likely to see someone pull this off soon.

I think one could also poll the GPIO often enough to detect a drip ( or even set it up as an inturpt? )
Pete has that part figured out in another thread some where i think